1. Field of the Invention
The present invention relates to a display device having a section for automatically setting the angle of visibility or contrast of a display screen in correspondence with the angle of the display screen for a user or the like.
2. Description of the Related Art
As is well known, an angle of visibility is present in a display device in the light of its nature. Further, it is experientially known that the visibility of the display screen changes even within the range of the angle of visibility depending on the angle formed by the user""s eye line and the display screen.
For example, it is experientially known that, in liquid crystal displays which are used for various electronic appliances as lightweight and thin display devices, a clearest view can be obtained when the angle formed by the user""s eye line and the display screen of the liquid crystal display is orthogonal, and that the visibility gradually declines as the display screen is tilted with respect to the user""s eye line.
A display device disclosed in JP-A-6-38136 is known as a display device for ameliorating such a change in the visibility corresponding to the angle formed by the user""s eye line and the display screen.
This display device is supported by an angle adjusting mechanism, and is provided with an angle detecting section for detecting a tilt angle of the display device with respect to the angle adjusting mechanism as well as a storage section for storing individual contrast data in correspondence with respective tilt angles. If the user tilts the display device, specific contrast data is read out from the storage section in correspondence with the tilt angle detected by the angle detecting section, and the contrast of the display screen is set on the basis of the contrast data.
Further, it is possible to change (adjust) the contrast data in the storage section for each tilt angle. If the user tilts the display device at a desired angle and effects an adjustment operation of the contrast at that tilt angle, the angle detecting section detects the tilt angle, and the storage section replaces the old contrast data corresponding to that tilt angle with newly adjusted contrast data, and stores the same. Accordingly, if the user tilts the display device at the desired angle after adjustment, the display is given with automatically adjusted contrast.
However, with the above-described conventional display device, if the user attempts to adjust the contrast appropriately with respect to a plurality of or all the tiltable angles, it has been necessary to consecutively tilt the display device and repeat the operation of contrast adjustment for the respective tilt angles. For this reason, a complicated operation is required for the user, and it cannot be said that the operational efficiency has been satisfactory.
Namely, the aforementioned contrast adjustment is effected in the procedure shown in the flowchart in FIG. 8. First, when the user tilts the display device at a desired angle (Step S200), this tilt angle xcex8 is detected by the angle detecting section (Step S202). Next, when the user effects an operation for adjusting the contrast to one corresponding to the tilt angle xcex8 (Step S204), the storage section stores the adjusted contrast data in correspondence with the angle xcex8 (Step S206). Then, a determination is made as to whether or not an instruction for termination of the adjustment has been given by the user (Step S208), and if the instruction for termination has not been given, contrast adjustment processing is repeated with respect to another tilt angle xcex8 starting with Step S200. Accordingly, if the user attempts to adjust the contrast with respect to a plurality of tilt angles xcex8, it has been necessary to change the contrast data one by one by repeating the operation in Steps S200 and S204 a plurality of times.
In other words, contrast adjustment is made as the user updates (rewrites) the contrast data stored in the storage section through a step-by-step operation. For this reason, as shown in FIG. 9, in order to adjust the contrast data (contrast values) M0, M1, M2, . . . , which have already been stored in the storage section in correspondence with the respective tilt angles xcex80,xcex81, xcex82, . . . , to appropriate contrast values CM0, CM1, CM2, . . . , the user must individually perform operations one by one in which the contrast value M0 corresponding to the tilt angle xcex80 is changed to CM0 in a first adjustment operation, the contrast value M1 corresponding to the tilt angle xcex81 is changed to CM1 in a second operation, the contrast value M2 corresponding to a next tilt angle xcex82 is changed to CM2 in a third operation, and so forth. Thus, there has been a problem in that a complicated operation is imposed on the user.
In addition, while the user is performing such a repeated operation, the user""s viewing position may become offset. Therefore, there can be cases where, even if the user thinks that he or she is performing the adjustment operation appropriately, the adjustment cannot be done appropriately as a result. Since readjustment is required in such a case as well, there has been a problem in the operational efficiency. Accordingly, because the viewing position is liable to become offset, not only is the operation troublesome, but there has been the problem that appropriate contrast adjustment cannot be effected easily.
The invention has been devised to overcome the above-described problems of the conventional art, and it is an object of the invention to provide a display device capable of setting an appropriate angle of visibility or contrast in correspondence with the angle of the display screen with respect to the user or the like, and of improving the operational efficiency of angle-of-visibility or contrast adjustment.
To attain the above object, in accordance with a first aspect of the invention, there is provided a display device which has a display screen and is supported by an angle adjusting mechanism, comprising: detecting section for detecting an angle formed by the display screen and the angle adjusting mechanism; and setting section for setting an angle of visibility of the display screen on the basis of information on an angle of visibility corresponding to the angle detected by the detecting section, wherein, in a state in which the display screen is set to one angle with respect to the angle adjusting mechanism, the setting section adjusts the angle of visibility at the one angle by adjusting the information on an angle of visibility corresponding to the one angle, and subsequently adjusts the information on an angle of visibility corresponding to remaining angles, to thereby automatically adjust the angles of visibility corresponding to the remaining angles.
In accordance with the above-described first aspect of the invention, when the user or the like tilts the display screen at one desired angle and gives an instruction for adjusting the angle of visibility to the setting section, the setting section adjusts the angle of visibility of the display screen on the basis of information on an angle of visibility corresponding to the one angle. Further, the setting section automatically effects the adjustment of the angles of visibility corresponding to the remaining angles on the basis of the adjustment value used at the time of the angle-of-visibility adjustment at the one angle. Consequently, as the user or the like merely gives an instruction for the angle-of-visibility adjustment for the one angle, the angle-of-visibility adjustment for the other (remaining) angles is automatically made. Hence, the angle-of-visibility adjustment can be made for all the directions by a simple operation. After the angle-of-visibility adjustment, as the user only tilts the display screen at a desired angle, the display at an appropriate angle of visibility is effected automatically.
In accordance with a second aspect of the invention, there is provided a display device which has a display screen and is supported by an angle adjusting mechanism, comprising: detecting section for detecting an angle formed by the display screen and the angle adjusting mechanism; and setting section for setting an angle of visibility of the display screen on the basis of information on contrast corresponding to the angle detected by the detecting section, wherein, in a state in which the display screen is set to one angle with respect to the angle adjusting mechanism, the setting section adjusts the angle of visibility at the one angle by adjusting the information on contrast corresponding to the one angle, and subsequently adjusts the information on contrast corresponding to remaining angles, to thereby automatically adjust the angles of visibility corresponding to the remaining angles.
In accordance with the above-described second aspect of the invention, it becomes possible for the user or the like to make angle-of-visibility adjustment for all the directions by a simple operation. After the angle-of-visibility adjustment, by merely tilting the display screen at a desired angle, the display at an appropriate angle of visibility is effected automatically.
For example, in a display device for effecting display by means of such as a liquid crystal display, a correlation exists between the contrast and the angle of visibility, and when the user or the like tilts the display screen at one desired angle and gives an instruction for adjusting the contrast, the setting section adjusts the angle of visibility of the display screen on the basis of information on contrast corresponding to the one angle.
Further, the setting section automatically effects the adjustment of the angles of visibility corresponding to the remaining angles by effecting contrast adjustment for the remaining angles on the basis of the adjustment value of the contrast used at the time of the angle-of-visibility adjustment at the one angle. Consequently, as the user or the like merely gives an instruction for the angle-of-visibility adjustment for the one angle, the angle-of-visibility adjustment for the other (remaining) angles is automatically made. Hence, the angle-of-visibility adjustment can be made for all the directions by a simple operation. After the angle-of-visibility adjustment, as the user only tilts the display screen at a desired angle, the display at an appropriate angle of visibility is effected automatically.
In accordance with a third aspect of the invention, there is provided a display device which has a display screen and is supported by an angle adjusting mechanism, comprising: detecting section for detecting an angle formed by the display screen and the angle adjusting mechanism; and setting section for setting the contrast of the display screen on the basis of information on contrast corresponding to the angle detected by the detecting section, wherein, in a state in which the display screen is set to one angle with respect to the angle adjusting mechanism, the setting section adjusts the contrast at the one angle by adjusting the information on contrast corresponding to the one angle, and subsequently adjusts the information on contrast corresponding to remaining angles, to thereby automatically adjust the contrast corresponding to the remaining angles.
In accordance with the above-described third aspect of the invention, when the user or the like tilts the display screen at one desired angle and gives an instruction for adjusting the contrast, the setting section adjusts the contrast of the display screen on the basis of information on contrast corresponding to the one angle. Further, the setting section automatically effects the adjustment of the contrast corresponding to the remaining angles on the basis of the adjustment value used at the time of the contrast adjustment at the one angle. Consequently, as the user or the like merely gives an instruction for the contrast adjustment for the one angle, the contrast adjustment for the other (remaining) angles is automatically made. Hence, the contrast adjustment can be made by a simple operation. After the contrast adjustment, as the user only tilts the display screen at an angle other than the aforementioned one angle, the display with appropriate contrast is effected automatically.
Namely, even with a display device whose angle of visibility does not change, the phenomenon is known in which the visibility of the display screen declines as the angle formed by the eye line of the user or the like and the display screen of the display device changes, and a situation similar to a case in which the angle of visibility is substantially narrowed is brought about by the decline in the visibility. With respect to such a decline in the visibility, a substantially appropriate angle of visibility is set by appropriately adjusting the contrast through the automatic contrast adjustment described above.
In a fourth aspect of the invention, in the display device according to any one of the first to third aspects of the invention, after adjusting the information on an angle of visibility or the information on contrast corresponding to the one angle, the setting section adjusts the information on an angle of visibility or the information on contrast corresponding to the remaining angles on the basis of an adjustment value of the information on an angle of visibility or an adjustment value of the information on contrast corresponding to the one angle as well as initial values which are preset in correspondence with respective variable angles of the display screen.
In a fifth aspect of the invention, in the display device according to the fourth aspect of the invention, the setting section effects the adjustment corresponding to the remaining angles by determining a difference between the adjustment value corresponding to the one angle and an initial value corresponding to the one angle among the initial values and by adding the difference to the respective initial values corresponding to the remaining angles.
In a sixth aspect of the invention, in the display device according to any one of the first, second, fourth, and fifth aspects of the invention, the display device has the display screen based on a liquid crystal display, and the setting section adjusts the orientation of the angle of visibility of the liquid crystal display.
The above and other objects, features and advantages of the present invention will become more apparent from the following detailed description of the invention when read in conjunction with the accompanying drawings.